1. Field of the Invention
This invention relates to a method for forming components from fiber-reinforced thermoplastic materials and is particularly concerned with forming such components from at least two pre-consolidated constituent parts at least one of which has to be re-shaped and at least one other of which provides a reinforcing function.
2. Description of the Prior Art
The aircraft industry makes wide use of fiber reinforced thermoplastic materials and many components of the above construction exist in that field. For example, conventional stiffening ribs have a web portion and a peripheral reinforced flange portion and a bulkhead may well include internal web stiffeners in addition to peripheral reinforced flange portions.
Traditionally such components are made by pre-consolidation of a sheet of material of a desired thickness for forming to the shape of the web portion and flanges, and pre-consolidation of one or more reinforcing sheets of a desired thickness. Firstly, the web portion sheet and possibly the reinforcing sheet is/are formed to shape in a mould tool and, secondly, the sheets are transferred to an assembly tool under appropriate heat and pressure for a desired period of time to fusion bond the sheets. During consolidation the sheets may be provided with a co-moulded adherent polymer layer in those areas that are eventually to be attached together to assist fusion bonding as disclosed in European published patent application EP-A-0320155.
This two stage process is therefore time consuming and costly in that separate mould and assembly tools are required.